Simplify/Cleanup MediaClient

chromecast/renderer/media/BUILD.gn

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 source_set("media") {
   sources = [
+    "cast_media_client.cc",
+    "cast_media_client.h",
     "media_caps_observer_impl.cc",
     "media_caps_observer_impl.h",
   ]
 
   deps = [
+    "//base",
     "//chromecast/common/media:interfaces",
     "//chromecast/media",
+    "//chromecast/media/cdm",
+    "//chromecast/public:public",
+    "//content/public/renderer",
+    "//media",
     "//ui/gfx/geometry",
   ]
 }